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farpd(8) [debian man page]

ARPD(8) 						    BSD System Manager's Manual 						   ARPD(8)

NAME

     farpd -- ARP reply daemon

SYNOPSIS

     farpd [-d] [-i interface] [net ...]

DESCRIPTION

     farpd replies to any ARP request for an IP address matching the specified destination net with the hardware MAC address of the specified
     interface, but only after determining if another host already claims it.

     Any IP address claimed by farpd is eventually forgotten after a period of inactivity or after a hard timeout, and is relinquished if the real
     owner shows up.

     This enables a single host to claim all unassigned addresses on a LAN for network monitoring or simulation.

     farpd exits on an interrupt or termination signal.

     Note: The program name farpd has been changed in Debian GNU/Linux from the original name (arpd) to avoid name clash with other ARP daemons.

     The options are as follows:

     -d      Do not daemonize, and enable verbose debugging messages.

     -i interface
	     Listen on interface.  If unspecified, farpd searches the system interface list for the lowest numbered, configured ``up'' interface
	     (excluding loopback).

     net     The IP address or network (specified in CIDR notation) or IP address ranges to claim (e.g. ``10.0.0.3'', ``10.0.0.0/16'' or
	     ``10.0.0.5-10.0.0.15''). If unspecified, farpd will attempt to claim any IP address it sees an ARP request for.  Mutiple addresses
	     may be specified.

FILES

     /var/run/farpd.pid

SEE ALSO

     pcapd(8), synackd(8)

BUGS

     farpd will respond too slowly to ARP requests for some applications. In order to ensure that it does not claim existing IP addresses it will
     send two ARP request and wait for a reply. This slowness affects the nmap network scanning tool, and possibly others, which uses by default
     ARP when scanning local networks. The answers from farpd will come after the tool has timeout waiting for the ARP replies and, consequently,
     IP addresses claimed by farpd will not be discovered.

     Additionally, farpd sends the ARP replies to the broadcast address of the network and not to the host that send the ARP request. Some systems
     and applications (notably nmap) will not handled these requests and expect directed ARP replies (i.e. targeted specifically to the host that
     sent the request and not to the network)

AUTHORS

     Dug Song <dugsong@monkey.org>, Niels Provos <provos@citi.umich.edu>

								  August 4, 2001

Check Out this Related Man Page

arpsend(8)							    Containers								arpsend(8)

NAME

       arpsend - send ARP requests

SYNOPSIS

       arpsend -D -e target_ip [ -e target_ip ...]  [-c count] [-w timeout] interface

       arpsend -U -i source_ip [-c count] [-w timeout] interface

DESCRIPTION

       Utility arpsend sends ARP packets on device interface to detect or update neighbours' ARP caches with a given IP.

COMMANDS

       Run utility with one of the following commands:

       -D     Send broadcast ARP request to detect neighbours with target_ip. You have to specify target_ip (-e option).

       -U     Send broadcast ARP request to update neighbours' ARP caches with source_ip. You have to specify source_ip (-i option).

OPTIONS

       -c count
	      Number of packets to send. Default is infinity.

       -w interval
	      Interval between packets, in seconds. Default is 1 second.

       -i source_ip_address
	      Set source IP address field in ARP packet.

       -e target_ip_address
	      Set  target  IP  address	field in ARP packet. Note that you can specify -e option multiple times to detect many IP addresses in one
	      utility call.

EXIT STATUS

       arpsend returns 0 upon successful execution. If something goes wrong, it returns an appropriate error code.

       1    EXC_USAGE
	      Usage error

       2    EXC_SYSTEM
	      System error

       3    EXC_RECV
	      ARP reply was received

EXAMPLES

       To send request on interface eth0 to detect any neighbour computers with IP 192.168.10.200:

	  arpsend -D -e 192.168.10.200 eth0

       To send request on interface eth0 to update neighbours' ARP caches with IP 192.168.10.200:

	  arpsend -U -i 192.168.10.200 eth0

NOTES

       Interface you use have to be arpable and not be loopback (i.e.  /sbin/ip link show interface should show neither NOARP nor  LOOPBACK  flags
       in interface parameters).

SEE ALSO

       vzctl(8).

LICENSE

       Copyright (C) 2000-2011, Parallels, Inc. Licensed under GNU GPL.

OpenVZ								    28 Jun 2011 							arpsend(8)
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